MAPPING THE SEA FLOOR USING NARROW-BEAM SONAR 



In the diagram above, ahull- 

 mounted, narrow-beam sonar 

 system is producing a continuous 

 profile of the sea floor as the 

 ship moves. The sample profile at 

 right, taken across a submarine 

 canyon, shows the rugged sea- 

 bottom topography typical of the 

 northern Gulf of the Farallones. 



Sonar beam 



NARROW-BEAM-SONAR PROFILE 



Ship's track 



18 Oceanography and Geology of the Gulf of the Farallones 



